fix(sdk-webview): reject file picker result when MIME type doesn't match accepted types

Some devices show .doc files in the picker even when only .docx was
requested (accept=".docx"). Passing the .doc URI to the WebView renderer
could cause a native crash. Now we check the actual MIME type of the
selected file against the accepted list and cancel the upload if it does
not match, preventing the renderer from receiving an unexpected file type.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

sdk-webview/src/main/java/com/xuqm/sdk/webview/XWebViewView.kt

@@ -360,6 +360,7 @@ fun XWebViewView(
     // <input type="file" capture> camera capture
     val pendingFileCallback = remember { mutableStateOf<ValueCallback<Array<Uri>>?>(null) }
     val pendingCameraUri = remember { mutableStateOf<Uri?>(null) }
+    val pendingAcceptMimes = remember { mutableStateOf<Array<String>?>(null) }
 
     val takePictureLauncher = rememberLauncherForActivityResult(
         ActivityResultContracts.TakePicture()
@@ -374,7 +375,28 @@ fun XWebViewView(
     val pickContentLauncher = rememberLauncherForActivityResult(GetContentWithMimeTypes()) { uri ->
         val cb = pendingFileCallback.value
         pendingFileCallback.value = null
-        cb?.onReceiveValue(if (uri != null) arrayOf(uri) else null)
+        if (uri == null) {
+            cb?.onReceiveValue(null)
+            return@rememberLauncherForActivityResult
+        }
+        // Validate that the selected file's actual MIME type is within the accepted list.
+        // Some devices show extra file types in the picker (e.g. .doc when only .docx was
+        // requested). Passing an unsupported type to the WebView renderer can cause a native
+        // crash. We accept the file only when its MIME type matches, or fall back to passing
+        // it through when we can't determine the type (to avoid blocking legitimate uploads).
+        val acceptedMimes = pendingAcceptMimes.value
+        val actualMime = uri.let { context.contentResolver.getType(it) }
+        val allowed = acceptedMimes.isNullOrEmpty() ||
+            acceptedMimes.any { accepted ->
+                accepted == "*/*" ||
+                (actualMime != null && (actualMime == accepted || actualMime.startsWith(accepted.substringBefore("*"))))
+            }
+        if (!allowed) {
+            android.util.Log.w("XWV", "Rejected file: actualMime=$actualMime not in accepted=$acceptedMimes")
+            cb?.onReceiveValue(null)
+        } else {
+            cb?.onReceiveValue(arrayOf(uri))
+        }
     }
 
     val shouldLaunchCamera = remember { mutableStateOf(false) }
@@ -605,6 +627,7 @@ fun XWebViewView(
                         pendingFileCallback.value = filePathCallback
 
                         val acceptMimes = resolvePickerMimeTypes(fileChooserParams.acceptTypes)
+                        pendingAcceptMimes.value = acceptMimes
                         val isCameraCapture = fileChooserParams.isCaptureEnabled &&
                             fileChooserParams.acceptTypes.any { it.contains("image") }
                         val isImageOnly = acceptMimes.all { it.startsWith("image/") || it == "image/*" }